University of Florida
Hearing Conservation Policy

 

BACKGROUND

The Occupational Safety and Health Administration (OSHA) has promulgated regulations limiting employee exposure to noise.  These regulations have been adopted by the State of Florida.  ACGIH and NIOSH have instituted more stringent guidelines which are adopted by UF. 

 

PROGRAM

The principal requirements are as follows:

 

1.               Noise surveys must be conducted to identify all employees exposed to an eight hour time weighted average (TWA) of 85dBA or greater (dBA is a sound level reading in decibels made on the A-weighted network of a sound level meter) using the 3dB exchange.

2.               A hearing conservation program must be instituted for all employees exposed to a TWA of 85dBA or greater. This consists in part of:

a.               Baseline and annual audiograms performed by either an otolaryngologist, audiologist, qualified physician or certified technician.

b.               An annual training program that explains the purpose and major components of the hearing conservation policy. This includes discussing with employees the hazardous effects of noise, the various types of hearing protection and how to wear them, as well as the purpose of the audiogram.

c.               Providing, without charge to employees, a choice of hearing protection (either earplug or earmuff).  The best hearing protection is the one that the employee will wear all the time because it is comfortable, effective and has minimal impact on communication.

3.               Any employee exposed to noise greater than 85dBA shall be provided with hearing protection, regardless of duration.

 

RESPONSIBILITIES

It is the responsibility of the various Division Directors to identify potential areas of concern in their units.  Environmental Health & Safety will conduct noise surveys to determine which work areas require participation in the hearing conservation program.

 

Once a particular job is identified as having high noise levels, the Division concerned shall inform personnel that a baseline audiogram and participation in a training program is required for all future appointments to this position.

 

The Speech and Hearing Clinic at Dauer Hall will provide audiograms and training.  A copy of the results will be furnished to the EH&S Division to continually evaluate the program.

 

It shall be the responsibility of the Division concerned to provide a choice of hearing protection devices to those employees requiring them and to insure that they are being worn.

 

Please note that the cost of testing and training is borne by the Employing Division. Hearing protection device costs shall be the responsibility of the department employing the worker.

 

SELECTION OF HEARING PROTECTORS

 

Hearing protection must be worn by all employees who are exposed to noise above 85dBA.  The hearing protector should reduce the noise level below an 8-hr TWA of 85 dBA.  All hearing protectors are assigned a noise reduction rating (NRR) which can be found on the individual package or box the hearing protectors came in.  This NRR is based on a dBC scale, although most sound measurements are given in a dBA scale.  To account for this difference, the NRR number must be reduced by a value of 7 to determine how much protection it will afford in the work environment.

 

The equation is as follows:  dBA’ = dBA – (NRR – 7).

where:  dBA’ = effective noise level for the hearing protector

               dBA = measured A-weighted noise level (sound level meter readings)

               NRR = noise reduction rating obtained on package

If the noise of a piece of equipment is measured at 96 dBA, a hearing protector with a NRR of at least 18 would be needed:

 

dBA’ = dBA  - (NRR – 7)

85 = 96 – (NRR – 7)

NRR – 7 = 96 – 85,

NRR = 11 + 7

NRR = 18.

 

In a case where the hearing protector does not offer enough protection, earmuffs and plugs can be worn together.  In this case, determine the effective NRR of the plugs by subtracting 7  and then add an additional 5dBA reduction.  This number is then subtracted from the 8-hr TWA to determine the actual exposure at the employee’s ear.  Again, this number should be less than 85dBA.

 

Remember, hearing protectors must be worn properly to provide maximum protection.

 

REFERENCES

 

1)     Noise and Hearing Conservation Manual, 1986, American Industrial Hygiene Association

2)     U.S. Department of Health and Human Services, Public Health Service, National Institute for Occupational Safety and Health.  NIOSH Criteria for a Recommended Standard, Occupational Noise Exposure

3)     U.S. Department of Labor, Occupational Safety and Health Administration.  29CFR1910.95, Occupational Noise Exposure Standard